Mulitple overflows and vulnerabilities exist in Ethereal which may allow an
attacker to crash the program or run arbitrary code.

Background

Quote from http://www.ethereal.com
"Ethereal is used by network professionals around the world for
troubleshooting, analysis, software and protocol development, and
education. It has all of the standard features you would expect in a
protocol analyzer, and several features not seen in any other product. Its
open source license allows talented experts in the networking community to
add enhancements. It runs on all popular computing platforms, including
Unix, Linux, and Windows."